The present invention relates to improved apparatus for and methods of magnetic resonance imaging, and more particularly to gastrointestinal magnetic resonance imaging.
Magnetic resonance imaging (MRI) has enjoyed enormous success, in part because of the excellent contrast in tissue images which it inherently produces. In addition, MRI does not expose the patient to ionizing radiation such as x-rays.
One application of x-rays still in widespread use is in the area of gastrointestinal imaging. The gastrointestinal (GI) tract is imaged by having the patient drink a suitable contrast material, such as a barium-containing compound, and acquiring x-ray images of the region of the gastrointestinal tract in which the contrast material is located. For example, esophageal imaging is carried out by having a patient swallow a barium-containing liquid, and by imaging the patient's esophagus while the liquid traverses the esophagus. Similar procedures are used for imaging other regions of the GI tract.
It would be highly desirable to obtain sufficient image data during the course of a GI study in order to create cine displays of the GI tract as it functions, e.g. during swallowing. X-ray exposure limits, however, create practical limitations on the extent to which data for GI cines can be acquired.
Accordingly, it is an object of the invention to provide a practical method for MRI studies of the GI tract.
Another object of the invention is to provide an MRI system which has features to facilitate the acquisition and display of cine MRI studies of the GI tract.
Another object of the invention is to provide a method for acquiring GI images by MRI and which can be displayed in a cine format to show GI tract anatomical function as well as structure.
It is still another object of the invention to provide improved MRI imaging techniques for imaging complex structures which do not lie substantially in a single image slice.